Chicken embryos are a valuable model for the selection of Bacillus subtilis for probiotic purposes

Harnessing probiotics capability to combat Salmonella Heidelberg and improve intestinal health in broilers

“…The individual and combined inhibitory potential of the probiotic strains against the growth of Salmonella Heidelberg ( SH ) was examined. The probiotic strains used included Saccharomyces boulardii (the same strain of the product Floratil, Merck S.A) (SB); Lactobacillus delbrueckii CNRZ 327 (LD) obtained from INRAE (National Institute for Agriculture, Food and Environment) collection; Lactococcus lactis lactis LLL01 (Uniclon) (LL) a non-dairy lactic acid bacteria, xylose fermenter, and a gamma-aminobutyric acid ( GABA ) producer; Lactiplantibacillus plantarum LP09 (Uniclon) (LP) isolated from cow milk in Bahia-Brazil, and Lacticaseibacillus acidophilus LA01 (Uniclon) (LA) isolated from milk in Bahia-Brazil to inhibit in vitro growth of SH by following a methodology described elsewhere ( Dos Reis et al, 2022 ). The combined use of all probiotic strains is denoted as the “blend.”…”

“…The SH used in this study was isolated from chickens by our laboratory, 10 μL of the SH solution at 10 8 UFC/mL concentration was added to 10 mL of warm liquid nutrient agar (10 5 UFC/mL), poured into the plates on the spot of the probiotic bacteria, the plates were incubated at 37°C for 24 h. The antagonistic capacity of the probiotic bacteria was determined as follows: very strong inhibition (zones larger than 20 mm in diameter); strong inhibition (from 15 to 19 mm); moderate (from 11 to 14 mm); weak (from 9 to 10 mm), and no inhibition (less than 9 mm) ( Dos Reis et al, 2022 ). The inhibition zones (mm) for individual components (SB, LD, LL, LP, LA) and combinations (LA+LP, LA+LL, LA+SB, LP+LL, LP+SP, LP+LD, LA+LD, LA+LP+SB, LA+LP+LL and the blend) were used for further statistical evaluation one-way ANOVA (95% confidence) comparing each component or association with the blend.…”